CHAPTER 13 CHANGING THE LIVING WORLD. A. Selective breeding-choosing only animals with desired...

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CHAPTER 13 CHANGING THE LIVING WORLD

A. Selective breeding-choosing only animals with desired traits and mating or crossing them; this has been done with all domesticated animals and many food crops and flowers and trees 1. hybridization-crossing dissimilar individuals to hopefully get the best of both buffalo and a cow to get a beefalo donkey and a horse 2. inbreeding-breeding of organisms with similar traits makes organisms more homozygous and allows mutant genes to get together to produce mutant organisms B. Polyploidy-having an extra set of chromosomes; only occurs in plants, produces new species which often have larger flowers and fruits

Using a restriction enzyme and DNA ligase to make recombinant DNA restriction fragments with sticky ends

Gel Electrophoresis

Polymerase Chain Reaction - PCRDNA polymerase for PCR was taken from bacteria that live in hot water; the primers are the key to which DNA gets replicated.

Cloning a Human Gene in a bacterial plasmid

ampR-is a gene for antibiotic resistance

Recombinant DNA

Cloning a Human Gene in a bacterial plasmid

transformation-putting the plasmid into the bacteria

Bacteria that did not get a plasmid die on the plate that contains ampicillin

Bacteria with a plasmid without the human DNA can make the enzyme to breakdown X-gal and they turn blue

Bacteria that have the human gene in their plasmid cannot make the enzyme to break down X-gal and they stay white

Overview of How Bacterial Plasmids Are Used to Clone Genes

semistarvation

Dolly and her surrogate mother

Hello Dolly

“Pharm” animals

Using restriction fragment patterns to distinguish DNA from different alleles; takes patience or luck

Restriction fragment analysis by Southern Blotting

alkaline solution draws through the gel removing and denaturing some of the DNA

Single stranded DNA is attachedto the paper.

Sequencing of DNA by the Sanger MethodStep 1 Make labeled cDNA strands with special nucleotides that

stop the chain when they are added

Sequencing of DNA by the Sanger Method Step 2 Different length strands are produced randomly with the ddNucleotides stopping the strand polymerization when they are added

Sequencing of DNA by the Sanger Method Step 3 The new DNA strands are separated by gel electrophoresis.

Sequencing of DNA by the Sanger Method Step 4: Read the sequence of the strands from the bands on the autoradiograph

G A C T G A A

G C

Alternative strategies for sequencing an entire genome.Celera used the maps and sequence data from the public consortium

DNA microarray for gene expression

Proteomics-study of the full sets of proteins encoded by genomesChallenges:More proteins than genesProteins differ with cell type and stateProteins are extremely variable in structure and function

DNA microarray for

gene expression

2,400 human genes shows which genes

are being made into

protein in this cell

RFLP markers close to a gene

A possible gene therapy procedure

Problems:In a multicellular organisms, it is difficult to get the gene into and expressed by enough cells to make a difference.We could eventually correct the defect in germ or embryonic cells but should we?

DNA fingerprints from a murder caseRFLP markers from satellite DNA with

“simple tandem repeats”

Pharmaceutical Productshuman insulinhuman growth factorplasminogen activator (clot busters)artificial vaccines

Currently only made by bacteria and viruses

Using the Ti plasmid as a vector forgenetic engineering in plants

Genetically modifiedGolden Rice with beta-carotene

Ordinary Rice

Banding patterns

Analyzing DNA

Injecting DNA into a cell

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